I had some of those little sheets of breath mints... awesome stuff.
I accidentally pulled 3 of them out of the little sleeve thing they were in and only needed one.
So, the extra two were laying in the soft sided six pack bag I carry my rain gear and lunch in.
I also inadvertently left a couple of dollars bills in there and then, as I was riding my bicycle home that night, it started raining hard.
Well, the bag isn't that rain proof, so the inside got a little moist. Those breath mints sheets were in contact with the dollar bills.
The next day the dollar bills wouldn't work in the vending machine. I realized they were tainted from the sticky residue of those breath mint sheets.
I laundered them in the sink with soap and water and all was good again.